Sensorless Monitoring of a Motor-Drive Machanical System Based on Adaptive Signal Decomposition

A method for estimating current harmonics of an induction motor is introduced which is used for sensorless monitoring of a mechanical system driven by the motor. The method is based on an adaptive signal representation and is proposed to extract weak harmonics from a noisy current signal, especially in the presence of additive interference caused by transient modulation waves. As an application, a rotor unbalance experiment of rotating machinery driven by an induction motor is carried out, The result shows that the eccentricity harmonic magnitude of a current signal obtained by the method represents the rotor unbalance conditions sensitively. Vibration analysis is used to validate the proposed method.

感应电机驱动的机械系统无传感器监测方法研究

提出一种应用于感应电机驱动的机械系统无传感器监测的谐波导纳估计方法。基于特别选定的基元函数 ,并结合遗传算法 ,给出一种自适应信号分解算法 ,用来提取电机电信号中的相关谐波 ,具有从强瞬态调制波干扰的信号中提取微弱谐波信息的优点 ,尤其是当瞬态调制波的载波频率与要提取的谐波频率相同时 ,仍可获得满意的结果。应用提出的方法 ,对感应电机驱动的机械系统转子失衡问题进行了实验研究 ,结果表明 ,获得的电机谐波导纳的偏心谐波幅值能够敏感地反映转子的失衡状态 ,从而可实现在无传感器条件下对电机驱动的机械系统进行状态监测和诊断。与振动法的对比实验证实了该方法的可行性。